KVM: Add last_host_tsc tracking back to KVM

[platform/adaptation/renesas_rcar/renesas_kernel.git] / arch / x86 / kvm / x86.c

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 2a59f76..39a57da 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2253,13 +2253,8 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 
        kvm_x86_ops->vcpu_load(vcpu, cpu);
        if (unlikely(vcpu->cpu != cpu) || check_tsc_unstable()) {
-               /* Make sure TSC doesn't go backwards */
-               s64 tsc_delta;
-               u64 tsc;
-
-               tsc = kvm_x86_ops->read_l1_tsc(vcpu);
-               tsc_delta = tsc - vcpu->arch.last_guest_tsc;
-
+               s64 tsc_delta = !vcpu->arch.last_host_tsc ? 0 :
+                               native_read_tsc() - vcpu->arch.last_host_tsc;
                if (tsc_delta < 0)
                        mark_tsc_unstable("KVM discovered backwards TSC");
                if (check_tsc_unstable()) {
@@ -2282,7 +2277,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 {
        kvm_x86_ops->vcpu_put(vcpu);
        kvm_put_guest_fpu(vcpu);
-       vcpu->arch.last_guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu);
+       vcpu->arch.last_host_tsc = native_read_tsc();
 }
 
 static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu,